I wouldn't consider #7 bad/black depending on the approach. Messaging every user in 1 min via bot, a little messed up, but if i got an interested PM, i am more likely to click and check it out. its more personal. Players are ALWAYS seeking new/better games.
Regardless, #7 is the most.effective approach getting your game out there when starting out. One should not care what the owners of another game. they are your competitons. Chances are if they post in a few forums, ect about your tactics, it will do damage your rep. Once your gamegets more known, those didiscussions on the net will get burried far in the SE results.
Not just games, but tons of niches do it. This dude on Twitter tagged me in a tweet about something. I seen it, checked his page, he tagged thousands of people one by one, with link, short desc, and image. Hell yeah, i checked it out. Imsged him, told him great tactic then shared his tweet. lol :)
whatever works, if i spammed the hell out of games and owners msged me, well I paid someone for referrals, will apologize and tell the owner I'll deactivate his account for referral account for spamming
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Maybe ill consult @Mik for advice regarding advertising of another project of mine of mine. lol